I mean... Yea. Yea it is. They want to:

1. Fill the thing with ads
2. Control the entire user experience
3. Track everything you do in that experience
4. Prevent users from accessing any low level system changes
5. Fill the thing with ads

They're not even being subtle about it:

“The Copilot is like the Start button,” Nadella explains. “It becomes the orchestrator of all your app experiences. So for example, I just go there and express my intent and it either navigates me to an application or it brings the application to the Copilot, so it helps me learn, query and create — and completely changes, I think, the user habits.”

That's exactly why they want control of it